Firearms are a known hazard to law enforcement officers. In 2016, one hundred and forty-three law enforcement officers died in the line of duty, and sixty-six of these deaths were attributed to lethal gunshot wounds. Law enforcement officers have worn ballistic vests for decades to reduce the risk of lethal gunshot wounds, but ballistic vests have limitations. In particular, ballistic vests protect torsos while leaving other body parts vulnerable to gunshot wounds.
The head is particularly vulnerable to gunshots, and known ballistic vests offer no head protection. Gunshot wounds to the head are associated with high risk of death or grave disability due to irreversible brain tissue damage. Ballistic helmets are available that can reduce head damage from gunshot wounds. However, police departments frequently limit the use of ballistic helmets because they can appear aggressive or militaristic to the public. Thus, ballistic helmets are generally only issued to Special Weapons and Tactics (SWAT) units in police departments. In addition, ballistic helmets can be heavy and cumbersome for constant wear while on duty.